| 5424907 | Solid electrolytic capacitors and method for manufacturing the same | June, 1995 | Kojima et al. | 361/532 |
| 6462936 | Solid electrolytic capacitor | October, 2002 | Fujimoto et al. | 361/525 |
| 6552896 | Solid electrolytic capacitor and method for manufacturing the same | April, 2003 | Igaki et al. | 361/523 |
| 6882519 | Flat aluminum electrolytic capacitor and method of manufacturing the same | April, 2005 | Uzawa et al. | 361/523 |
| 6912117 | Solid electrolytic capacitor and method of manufacturing the same | June, 2005 | Arai et al. | 361/523 |
| 7135754 | Chip type solid electrolytic capacitor having a small size and a simple structure | November, 2006 | Sano et al. | 257/528 |
| 7139163 | Solid electrolytic capacitor | November, 2006 | Sawano | 361/540 |
| 7158366 | Solid electrolytic capacitor | January, 2007 | Kobayashi et al. | 361/523 |
| JP2000340463 | December, 2000 | |||
| JP2001110676 | April, 2001 | |||
| JP200345753 | February, 2003 |
THIS APPLICATION IS A U.S. NATIONAL PHASE APPLICATION OF PCT INTERNATIONAL APPLICATION PCT/JP2005/007007, filed Apr. 11, 2005
The present invention relates to a solid electrolytic capacitor including solid electrolyte made of conductive polymer for use in various electronic devices, and to a method of manufacturing the capacitor.
According to high-frequency operations of electronic apparatuses, capacitors used in the apparatuses have been required to have excellent impedance characteristics in high frequencies. For this requirement, solid electrolytic capacitors including solid electrolytes made of conductive polymer having large conductivities.
FIG. 22 is a perspective view of conventional solid electrolytic capacitor 1100 disclosed in Japanese Patent Laid-Open Publication No. 2000-340463. FIG. 23 is a perspective view of capacitor 1100 . FIG. 24 is a perspective view of capacitor element 1030 of capacitor 1100 .
As shown in FIG. 24, in capacitor element 1030 , a surface of anode body 1031 made of valve metal, such as aluminum foil, is anodized to provide a dielectric oxide layer, and is divided into cathode portion 1034 and anode portion 1033 with resist 1032 having an insulating property. Solid electrolyte layer 1035 is formed on a surface of cathode portion 1034 . Cathode layer 1036 made of carbon and silver paste is formed on solid electrolyte layer 1035 .
Anode portion 1033 of capacitor element 1030 is placed on a connecting surface of anode terminal 1037 , and cathode layer 1036 is placed on a connecting surface of cathode terminal 1038 . Connecting portions 1037 A of the connecting surface of anode terminal 1037 are folded and joined to anode portion 1033 by resistance welding. Cathode layer 1036 is connected to the connecting surface of cathode terminal 1038 with conductive silver paste. Guides 1038 A are formed by bending portions of the connecting surface of cathode terminal 1038 .
Insulating resin package 1039 accommodates capacitor element 1030 , anode terminal 1037 connected to the element, and cathode terminal 1038 connected to the element to allow anode terminal 1037 and cathode terminal 1038 to have respective portions exposing to the outside. The portions of anode terminal 1037 and cathode terminal 1038 exposing to the outside of resin package 1039 are bent along respective sides to the bottom of resin package 1039 , thus providing outer terminals 1037 B and 1038 B, respectively.
In conventional solid electrolytic capacitor 1100 , anode terminal 1037 and cathode terminal 1038 have complex structures, thus being a factor raising a cost. Further, anode terminal 1037 and cathode terminal 1038 have considerable lengths from anode portion 1033 and cathode portion 1034 of capacitor element 1030 to outer terminals 1037 B and 1038 B, thus providing solid electrolytic capacitor 1100 with a large equivalent series inductance (ESL) and a large equivalent series resistance (ESR). They prevent the capacitor from being used around a CPU of a personal computer, which requires a small ESL, a large noise suppressing performance, and an excellent transient response to deal with high frequencies.
A solid electrolytic capacitor includes a flat-shaped anode terminal having a first surface connected to an anode portion of a capacitor element and having a second surface opposite to the first surface, a flat-shaped cathode terminal having a first surface connected to a cathode layer of the capacitor element and having a second surface opposite to the first surface thereof, and an insulating resin package accommodating the capacitor element, the anode terminal, and the cathode terminal. The second surface of the cathode terminal is flush with the second surface of the anode terminal. The second surface of the anode terminal and the second surface of the cathode terminal expose to an outside of the resin package. The anode terminal includes a first thick portion and a first thin portion thinner than the first thick portion. The first thick portion has the second surface of the anode terminal and a portion of the first surface of the anode terminal. The first thin portion has a portion of the first surface of the anode terminal and being connected to the first thick portion. The cathode terminal includes a second thick portion and a second thin portion thinner than the second thick portion. The second thick portion has the second surface of the cathode terminal and a portion of the first surface of the cathode terminal. The second thin portion has a portion of the first surface and being connected to the second thick portion.
This solid electrolytic capacitor has a small equivalent series inductance, and is stably mountable to a mount body.
FIG. 1A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 1 of the present invention.
FIG. 1B is a front view of the solid electrolytic capacitor according to Embodiment 1.
FIG. 1C is a bottom view of the solid electrolytic capacitor according to Embodiment 1.
FIG. 1D is a side view of the solid electrolytic capacitor according to Embodiment 1.
FIG. 1E is a perspective view of the solid electrolytic capacitor mounted to the mount body according to Embodiment 1.
FIG. 2 is a perspective view of a capacitor element of the solid electrolytic capacitor according to Embodiment 1.
FIG. 3A is a plan view of a substrate used for manufacturing the solid electrolytic capacitor according to Embodiment 1.
FIG. 3B is a cross sectional view of the substrate at line 3 B- 3 B shown in FIG. 3A.
FIG. 4A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 2 of the invention.
FIG. 4B is a front view of the solid electrolytic capacitor according to Embodiment 2.
FIG. 4C is a bottom view of the solid electrolytic capacitor according to Embodiment 2.
FIG. 4D is a side view of the solid electrolytic capacitor according to Embodiment 2.
FIG. 5 is a perspective view of a capacitor element of the solid electrolytic capacitor according to Embodiment 2.
FIG. 6A is a plan view of a substrate used for manufacturing the solid electrolytic capacitor according to Embodiment 2.
FIG. 6B is a cross sectional view of the substrate at line 6 B- 6 B shown in FIG. 6A.
FIG. 7A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 3 of the invention.
FIG. 7B is a front view of the solid electrolytic capacitor according to Embodiment 3.
FIG. 7C is a bottom view of the solid electrolytic capacitor according to Embodiment 3.
FIG. 7D is a side view of the solid electrolytic capacitor according to Embodiment 3.
FIG. 8A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 4 of the invention.
FIG. 8B is a front view of the solid electrolytic capacitor according to Embodiment 4.
FIG. 8C is a bottom view of the solid electrolytic capacitor according to Embodiment 4.
FIG. 8D is a side view of the solid electrolytic capacitor according to Embodiment 4.
FIG. 9A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 5 of the invention.
FIG. 9B is a front view of the solid electrolytic capacitor according to Embodiment 5.
FIG. 9C is a bottom view of the solid electrolytic capacitor according to Embodiment 5.
FIG. 9D is a side view of the solid electrolytic capacitor according to Embodiment 5.
FIG. 10A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 6 of the invention.
FIG. 10B is a front view of the solid electrolytic capacitor according to Embodiment 6.
FIG. 10C is a bottom view of the solid electrolytic capacitor according to Embodiment 6.
FIG. 10D is a side view of the solid electrolytic capacitor according to Embodiment 6.
FIG. 11 is a perspective view of a capacitor element of the solid electrolytic capacitor according to Embodiment 6.
FIG. 12A is a plan view of a substrate used for manufacturing the solid electrolytic capacitor according to Embodiment 6.
FIG. 12B is a cross sectional view of the substrate at line 12 B- 12 B shown in FIG. 12A.
FIG. 13A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 7 of the invention.
FIG. 13B is a front view of the solid electrolytic capacitor according to Embodiment 7.
FIG. 13C is a bottom view of the solid electrolytic capacitor according to Embodiment 7.
FIG. 13D is a side view of the solid electrolytic capacitor according to Embodiment 7.
FIG. 14A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 8 of the invention.
FIG. 14B is a front view of the solid electrolytic capacitor according to Embodiment 8.
FIG. 14C is a bottom view of the solid electrolytic capacitor according to Embodiment 8.
FIG. 14D is a side view of the solid electrolytic capacitor according to Embodiment 8.
FIG. 15A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 9 of the invention.
FIG. 15B is a front view of the solid electrolytic capacitor according to Embodiment 9.
FIG. 15C is a bottom view of the solid electrolytic capacitor according to Embodiment 9.
FIG. 15D is a side view of the solid electrolytic capacitor according to Embodiment 9.
FIG. 16A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 10 of the invention.
FIG. 16B is a front view of the solid electrolytic capacitor according to Embodiment 10.
FIG. 16C is a bottom view of the solid electrolytic capacitor according to Embodiment 10.
FIG. 16D is a side view of the solid electrolytic capacitor according to Embodiment 10.
FIG. 17A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 11 of the invention.
FIG. 17B is a front view of the solid electrolytic capacitor according to Embodiment 11.
FIG. 17C is a bottom view of the solid electrolytic capacitor according to Embodiment 11.
FIG. 17D is a side view of the solid electrolytic capacitor according to Embodiment 11.
FIG. 18A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 12 of the invention.
FIG. 18B is a front view of the solid electrolytic capacitor according to Embodiment 12.
FIG. 18C is a bottom view of the solid electrolytic capacitor according to Embodiment 12.
FIG. 18D is a side view of the solid electrolytic capacitor according to Embodiment 12.
FIG. 18E is a perspective view of another solid electrolytic capacitor according to Embodiment 12.
FIG. 19A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 13 of the invention.
FIG. 19B is a front view of the solid electrolytic capacitor according to Embodiment 13.
FIG. 19C is a bottom view of the solid electrolytic capacitor according to Embodiment 13.
FIG. 19D is a side view of the solid electrolytic capacitor according to Embodiment 13.
FIG. 20A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 14 of the invention.
FIG. 20B is a front view of the solid electrolytic capacitor according to Embodiment 14.
FIG. 20C is a bottom view of the solid electrolytic capacitor according to Embodiment 14.
FIG. 20D is a side view of the solid electrolytic capacitor according to Embodiment 14.
FIG. 21A is a plan view of a solid electrolytic capacitor according to Exemplary Embodiment 15 of the invention.
FIG. 21B is a front view of the solid electrolytic capacitor according to Embodiment 15.
FIG. 21C is a bottom view of the solid electrolytic capacitor according to Embodiment 15.
FIG. 21D is a side view of the solid electrolytic capacitor according to Embodiment 15.
FIG. 22 is a view of a conventional solid electrolytic capacitor.
FIG. 23 is a perspective view of the conventional solid electrolytic capacitor.
FIG. 24 is a perspective view of a capacitor element of the conventional solid electrolytic capacitor.
FIGS. 1A to 1D show solid electrolytic capacitor 101 according to Exemplary Embodiment 1 of the present invention. FIG. 1B is a front view of solid electrolytic capacitor 101 . FIGS. 1A, 1 C, and 1 D are a plan view seen from direction IA, a bottom view seen from direction IC, and a side view seen from direction ID of solid electrolytic capacitor 101 shown in FIG. 1B, respectively. FIG. 2 is a perspective view of capacitor element 1 of solid electrolytic capacitor 101 . FIG. 1E is a perspective view of solid electrolytic capacitor 101 mounted to mount body 701 .
As shown in FIG. 2, capacitor element 1 has a substantially flat plate shape. A surface of anode body 2 made of valve metal, such as aluminum foil, is roughened and anodized, thus providing dielectric oxide layer 2 A on the surface. Resist 3 having an insulating property is provided on dielectric oxide layer 2 A, and divides anode body 2 into cathode portion 5 and anode portion 4 . Solid electrolyte layer 6 made of conductive polymer is provided on dielectric oxide layer 2 A of cathode portion 5 , and cathode layer 7 made of carbon and silver paste is placed on solid electrolyte layer 6 .
According to Embodiment 1, five capacitor elements 1 are stacked so that anode portion 4 of one of capacitor elements 1 is placed on anode lead frame 8 . Guides 8 A provided at both side ends of anode lead frame 8 are folded to wrap anode portions 4 of all of five capacitor elements 1 , and are joined unitarily to anode portions 4 at junctions 8 B by laser welding.
Cathode portions 5 of the five stacked capacitor elements 1 are placed over cathode lead frame 9 via a conductive adhesive. Five capacitor elements 1 are positioned and fixed with guides 9 A at both side ends and guide 9 B at a distal end of cathode lead frame 9 , and are joined unitarily. Thus, plural capacitor elements 1 , anode lead frame 8 , and cathode lead frame 9 unitarily assembled, providing capacitor element unit 2101 .
Anode terminal 10 has thick portion 10 E at the center thereof and thin portions 10 A. Thin portions 10 A are thinner than thick portion 10 E and are provided at both sides of thick portion 10 E. Thin portions 10 A are formed in anode terminal 10 by providing recesses 10 H in surface 10 G opposite to surface 10 F facing capacitor elements 1 . Surface 10 F of anode terminal 10 including thick portion 10 E and thin portions 10 A is flat. Thin portions 10 A have portions of surface 10 F of anode terminal 10 , and thick portion 10 E has a portion of surface 10 F. Anode lead frame 8 of capacitor element unit 2101 is placed on surface 10 F of anode terminal 10 , and is connected to anode terminal 10 at junctions 10 B inside thin portions 10 A by laser welding.
Cathode terminal 11 has thick portion 11 E at the center thereof and thin portions 11 A. Thin portions 11 A are thinner than thick portion 11 E and are connected at both sides of thick portion 11 E. Thin portions 11 A are formed in cathode terminal 11 by providing recesses 11 H in surface 11 G opposite to surface 11 F facing capacitor elements 1 . Surface 11 F of cathode terminal 11 including thick portion 11 E and thin portions 11 A is flat. Thin portions 11 A have portions of surface 11 F of cathode terminal 11 , and thick portion 11 E has a portion of surface 11 F. Cathode lead frame 9 of capacitor element unit 2101 is places on surface 11 F of cathode terminal 11 , and is connected to cathode terminal 11 at junctions 11 B inside thin portions 11 A by laser welding.
Thin portions 10 A and 11 A are arranged in direction D 2 perpendicular to direction D 1 in which anode terminal 10 and cathode terminal 11 are arranged. Thick portion 11 E of cathode terminal 11 is provided between thin portions 11 A.
Resin package 12 having an insulating property accommodates capacitor element unit 2101 therein to allow surfaces 10 G and 11 G of anode terminal 10 and cathode terminal 11 to expose to the outside. According to Embodiment 1, resin package 12 is made of epoxy resin. Capacitor 101 is mounted to mount body 701 , such as a wiring board, as shown in FIG. 1E. In this case, surfaces 10 G and 11 G function as mounting surfaces.
FIG. 3A is a plan view of substrate 13 having a hoop shape for providing plural anode terminals 10 and cathode terminals 11 . FIG. 3B is a cross sectional view of substrate 13 at line 3 B- 3 B shown in FIG. 3A. Substrate 13 is made of copper alloy, and has feed holes 13 A formed therein for intermittent feeding. The anode terminals 10 and cathode terminals 11 are formed consecutively in substrate 13 at predetermined intervals. Plural capacitor element units 2101 are joined onto respective ones of anode terminals 10 and cathode terminals 11 and are accommodated in resin packages 12 having an insulating property, respectively. Then, anode terminals 10 and cathode terminals 11 are removed from substrate 13 , thus providing plural chip capacitors 101 .
Substrate 13 having anode terminals 10 and cathode terminals 11 formed therein is formed by etching a metal plate. The etching removes unnecessary portions and thins the both sides of anode terminals 10 and cathode terminals 11 , thus providing thin portions 10 A and 11 A simultaneously. Thickness difference 10 J between thin portions 10 A and thick portion 10 E and thickness difference 11 J between thin portions 11 A and thick portion 11 E are determined to be not less than 80 μm. This dimension of each of differences 10 J and 11 J is necessary for allowing insulating resin package 12 to flow and sufficiently fill recesses 10 H and 11 H when capacitor element unit 2101 is accommodated. The dimension of differences 10 J and 11 J may be increased to such an extent that terminals 10 A and 11 A do not function as connecting terminals.
Solid electrolytic capacitor 101 according to Embodiment 1 allows anode portion 4 and cathode portion 5 of capacitor element 1 to be drawn out to the outside in a short distance through anode terminal 10 and cathode terminal 11 having flat plate shapes, thereby having a small equivalent series resistance (ESR) and a small equivalent series inductance (ESL). The ESL of solid electrolytic capacitor 101 was 800 pH, which was approximately a half of an ESL of 1500 pH of conventional solid electrolytic capacitor 1100 shown in FIGS. 22 to 24.
Anode terminal 10 and cathode terminal 11 are connected with anode lead frame 8 and cathode lead frame 9 of capacitor element unit 2101 at junctions 10 B and 11 B inside thin portions 10 A and 11 A at both sides of the center thick portions 10 E and 11 E by laser welding, respectively. Welding spots of these junctions are covered with resin package 12 , thus providing an excellent external finish. This avoids a possibility of mounting defect attributable to improper contact caused by the welding spots in a mounting process, thereby providing the capacitor with a high reliability.
According to Embodiment 1, anode body 2 of capacitor element 1 is made of aluminum foil, but is not limited to it. The anode body may be made of other valve metal, such as a foil or a sintered body of tantalum or niobium, a combination of them.
Substrate 13 has the hoop shape made of copper alloy to obtain anode terminals 10 and cathode terminals 11 , but may be made of other material and may have other shape.
Thin portions 10 A and 11 A of anode terminals 10 and cathode terminals 11 are formed by the etching. The thin portions may be made by press forming.
According to Embodiment 1, plural capacitor elements 1 are stacked and jointed to anode lead frame 8 and cathode lead frame 9 to provide capacitor element unit 2101 , and then connected to anode terminal 10 and cathode terminal 11 . However, the structure is not limited to that of this embodiment. One or more capacitor elements 1 may be connected directly to anode terminal 10 and cathode terminal 11 . This can further reduce the ESL. The number of capacitor elements 1 provided in capacitor element unit 2101 is not necessarily limited to five, but may be determined to obtain a predetermined capacitance.
FIGS. 4A to 4D show solid electrolytic capacitor 5101 according to Exemplary Embodiment 2 of the invention. FIG. 4B is a front view of solid electrolytic capacitor 5101 . FIGS. 4A, 4 C, 4 D are a plan view seen from direction IVA, a bottom view seen from direction IVC, and a side view seen from direction IVD of solid electrolytic capacitor 5101 shown in FIG. 4B, respectively. FIG. 5 is a perspective view of capacitor element 501 of solid electrolytic capacitor 5101 .
As shown in FIG. 5, capacitor element 501 has a substantially flat plate shape as shown in FIG. 5. A surface of anode body 502 made of valve metal, such as aluminum foil is roughened and anodized to provide dielectric oxide layer 502 A on the surface. Resist 503 having an insulating property is provided on dielectric oxide layer 502 A to divide anode body 502 into cathode portion 505 and anode portion 504 . Solid electrolyte layer 506 is provided on dielectric oxide layer 502 A of cathode portion 505 , and cathode layer 507 made of carbon and silver paste is placed on solid electrolyte layer 506 .
According to Embodiment 2, five capacitor elements 501 are stacked so that anode portion 504 of one of capacitor elements 501 is positioned on anode lead frame 508 . Guides 508 A provided at both side ends of anode lead frame 508 are folded to wrap anode portions 504 of all of five capacitor elements 501 , and are joined unitarily to anode portions 504 at junctions 508 B by laser welding.
Cathode portions 505 of the five stacked capacitor elements 501 are placed over cathode lead frame 509 via a conductive adhesive. Five capacitor elements 501 are positioned and fixed by guides 509 A at both side ends and guide 509 B at a distal end of cathode lead frame 509 , and are joined unitarily. Plural capacitor elements 501 , anode lead frame 508 , and cathode lead frame 509 unitarily assembled in the above manner provide capacitor element unit 5101 A.
Anode terminal 510 has thick portion 510 E at the center thereof and thin portions 510 A. Thin portions 510 A are thinner than thick portion 510 E, and are connected to both sides of thick portion 510 E. Thin portions 510 A are formed in anode terminal 510 by providing recesses 510 H in surface 510 G opposite to surface 510 F facing capacitor elements 501 . Surface 510 F of anode terminal 510 including thick portion 510 E and thin portions 510 A is flat. Thin portions 510 A have portions of surface 510 F of anode terminal 510 , and thick portion 510 E has a portion of surface 510 F. Anode lead frame 508 of capacitor element unit 5101 A is placed on surface 510 F of anode terminal 510 , and is connected to anode terminal 510 at junctions 510 B inside thin portions 510 A by laser welding. Protruding portion 510 C having surface 510 G of anode terminal 510 extending outward protrudes from resin package 512 . Surface 510 G functions as a mounting surface upon being mounted onto a mount body, such as a wiring board.
Surface 511 G of cathode terminal 511 opposite to surface 511 F facing capacitor element 501 is flush with surface 510 G of anode terminal 510 . Surface 511 G of cathode terminal 511 is arranged as close to surface 510 F of anode terminal 510 as possible. Distance L 1 between surface 511 G of cathode terminal 511 and surface 51 -G of anode terminal 510 is not shorter than 1 mm, and preferably is 1 mm. The distance, being less than 1 mm, may cause a current leakage across the surfaces. Cathode terminal 511 has thick portion 511 E having surface 511 G and thin portion 511 A. Thin portion 511 A is thinner than thick portion 511 E, and extends in a direction opposite to anode terminal 510 . Surface 511 F of cathode terminal 511 including thick portion 511 E and thin portion 511 A is flat. Thin portion 511 A has a portion of surface 511 F of cathode terminal 511 , and thick portion 511 E has a portion of surface 511 F. Surface 511 K of thin portion 511 A is covered with resin package 512 and does not expose, thus not functioning as a mounting surface arranged to be mounted onto the mount body. Cathode lead frame 509 of the capacitor element unit 5101 A is placed on surface 511 F of cathode terminal 511 , and is connected to cathode terminal 511 at junctions 511 B inside thin portion 511 A by laser welding.
Resin package 512 having an insulating property accommodates capacitor element unit 5101 A unitarily and allows protruding portion 510 C and surface 510 G of anode terminal 510 and surface 511 G of cathode terminal 511 to expose to the outside. According to Embodiment 2, resin package 512 is made of epoxy resin.
FIG. 6A is a plan view of substrate 513 having a hoop shape for providing plural anode terminals 510 and cathode terminals 511 . FIG. 6B is a cross sectional view of substrate 513 at line 6 B- 6 B shown in FIG. 6A. Substrate 513 is made of copper alloy, and has feed holes 513 A formed therein for intermittent feeding. The anode terminals 510 and cathode terminals 511 are formed consecutively in substrate 513 at predetermined intervals. Plural capacitor element units 5101 A are placed on and joined to respective ones of anode terminals 510 and cathode terminals 511 , and are covered with resin packages 512 , respectively. Then, anode terminals 510 and cathode terminals 511 are removed from substrate 513 to provide plural chip capacitors 5101 .
Substrate 513 having anode terminals 510 and cathode terminals 511 is formed by etching a metal plate. The etching simultaneously provides thin portions 510 A and 511 A by removing unnecessary portions and thinning the both sides of anode terminals 510 and cathode terminals 511 . Thickness differences 510 J between thin portion 510 A and thick portion 510 E and thickness differences 511 J between thin portion 511 A and thick portion 511 E are determined to be not less than 80 μm. This dimension of differences 510 J and 511 J is necessary for allowing resin package 512 to flow sufficiently in recesses 510 H and on surface 511 K when capacitor element unit 5101 A is accommodated.
Solid electrolytic capacitor 5101 according to Embodiment 2 allows both anode portion 504 and cathode portion 505 of capacitor element 501 to be drawn out to the outside in a short distance through anode terminal 510 and cathode terminal 511 having flat plate shapes. Further, surface 511 G of cathode terminal 511 is arranged as close to surface 510 G of anode terminal 510 as possible in order to reduce the distance between anode terminal 510 and cathode terminal 511 to a shortest possible value, thereby providing a small equivalent series resistance (ESR) and a small equivalent series inductance (ESL). The ESL of solid electrolytic capacitor 5101 of Embodiment 2 was 500 pH, which was approximately one third of an ESL of 1500 pH of conventional solid electrolytic capacitor 1100 shown in FIGS. 22 to 24.
Anode terminal 510 and cathode terminal 511 are connected with anode lead frame 508 and cathode lead frame 509 of capacitor element unit 5101 A at junctions 510 B and 511 B inside thin portions 510 A and 511 A by laser welding, respectively. Welding spots of these junctions are covered with resin package 512 , thus providing an excellent external finish. This avoids a possibility of mounting defect attributable to improper contact caused by the welding spots in a mounting process, thereby providing the capacitor with a high reliability.
Surface 510 G of anode terminal 510 has protruding portion 510 C extending outward. This structure allows a solder fillet to be observable easily from above when the capacitor is soldered to be mounted to a mount body, such as a wiring board, thereby providing the capacitor with a high reliability of soldering.
According to Embodiment 2, anode body 502 of capacitor element 501 is made of aluminum foil, but is not limited to it. The anode body may be made of other valve metal of a foil or a sintered body of tantalum or niobium, a combination of them.
Substrate 513 has the hoop shape made of copper alloy to obtain anode terminals 510 and cathode terminals 511 , but may be made of other material and may have another shape.
Thin portions 510 A and 511 A of anode terminals 510 and cathode terminals 511 are formed by the etching. The thin portions may be formed by press-forming.
According to Embodiment 2, plural capacitor elements 501 are stacked and jointed to anode lead frame 508 and cathode lead frame 509 to provide capacitor element unit 5101 A, and then, are connected to anode terminal 510 and cathode terminal 511 . However, the structure is not limited to that of this embodiment. One or more capacitor elements 501 may be connected directly to anode terminal 510 and cathode terminal 511 . This can further reduce the ESL. The number of capacitor elements 501 provided in capacitor element unit 5101 A is not necessarily five, but may be determined to obtain a predetermined capacitance.
FIGS. 7A to 7D show solid electrolytic capacitor 5102 according to Exemplary Embodiment 3 of the invention. FIG. 7B is a front view of solid electrolytic capacitor 5102 . FIG. 7A, FIG. 7C and FIG. 7D are a plan view seen from direction VIIA, a bottom view seen from direction VIIC, and a side view seen from direction VIID of solid electrolytic capacitor 5102 shown in FIG. 7B. The same components as those of embodiment 2 will be denoted by the same reference numerals, and their detailed description is omitted.
Lower surface 514 G of cathode terminal 514 is arranged to be flush with lower surface 510 G (a mounting surface when mounted to a mount body, such as a wiring board) of anode terminal 510 , and is positioned as close to lower surface 510 G of anode terminal 510 as possible. Distance L 2 between surface 514 G of cathode terminal 514 and surface 510 G of anode terminal 510 is not less than 1 mm, and preferably is 1 mm. The distance being less than 1 mm may cause a current leakage across the surfaces. Cathode terminal 514 includes thick portion 514 E having surface 514 G and thin portion 514 A. Thin portion 514 A is thinner than thick portion 514 E, and extends from thick portion 514 E in a direction opposite to anode terminal 510 . Surface 514 K of thin portion 514 A opposite to a surface of the thin portion facing capacitor element 501 is covered with resin package 512 and does not expose, thus not functioning as a mounting surface arranged to be mounted to the mount body. Cathode terminal 514 includes mounting portion 514 C at an end of thin portion 514 A opposite to anode terminal 510 . The mounting portion 514 C has lower surface 514 L functioning as a mounting surface when the capacitor is mounted. Surface 514 L is flush with surfaces 510 G and 514 G. Mounting portion 514 C extends outward to provide protruding portion 514 D of cathode terminal 514 protruding from resin package 512 .
Mounting portion 514 C of cathode terminal 514 allows solid electrolytic capacitor 5102 according to Embodiment 3 to have the mounting surfaces provided at both ends, i.e., under anode terminal 510 and cathode terminal 514 , thereby allowing the capacitor to be mounted stably on the mount body Mounting portion 514 C of cathode terminal 514 has protruding portion 514 D extending outward. This structure allows a solder fillet to be observable easily from above, similarly to protruding portion 510 C of anode terminal 510 , when the capacitor is soldered to be mounted to the mount body, thereby providing the capacitor with a high reliability of soldering.
Solid electrolytic capacitor 5102 according to Embodiment 3 has a small equivalent series resistance (ESR) and a small equivalent series inductance (ESL) similarly to solid electrolytic capacitor 5101 of Embodiment 2. The ESL of solid electrolytic capacitor 5102 of Embodiment 3 was 500 pH, which was one third of an ESL of 1500 pH of conventional solid electrolytic capacitor 1100 shown in FIGS. 22 to 24.
FIGS. 8A to 8D show solid electrolytic capacitor 5103 according to Exemplary Embodiment 4 of the invention. FIG. 8B is a front view of solid electrolytic capacitor 5103 . FIGS. 8A, 8 C, and 8 D are a plan view seen from direction VIIIA, a bottom view seen from direction VIIIC, and a side view seen from direction VIIID of solid electrolytic capacitor 5103 shown in FIG. 8B. The same component as those of Embodiment 3 will be denoted by the same reference numerals, and their detailed description will be omitted.
Anode terminal 515 includes thick portion 515 E at the center thereof and thin portions 515 A. Thin portions 515 A are thinner than thick portion 515 E, and are connected to both sides of thick portion 515 E. Thin portions 515 A are formed in anode terminal 515 by providing recesses 515 H in surface 515 G opposite to surface 515 F facing capacitor elements 501 . Surface 515 F of anode terminal 515 including thick portion 515 E and thin portions 515 A is flat. Thin portions 515 A have portions of surface 515 F of anode terminal 515 , and thick portion 515 E has a portion of surface 515 F. Anode lead frame 508 of capacitor element unit 5101 A is placed on surface 515 F of anode terminal 515 , and is connected to anode terminal 515 at junctions 515 B inside thin portions 515 A by laser welding. Surface 515 G functions as a mounting surface when being mounted to a mount body, such as a wiring board. Surface 515 G of anode terminal 515 extends outward, providing anode terminal 515 with protruding portion 515 C protruding from resin package 512 . Protruding portion 515 C corresponds to protruding portion 510 C of anode terminal 510 of Embodiments 2 and 3. Protruding portion 515 C is bent upward along a side surface (i.e., an exterior surface) of resin package 512 , having a shape extending along an exterior of resin package 512 .
Lower surface 516 G of cathode terminal 516 is arranged to be flush with lower surface 515 G of anode terminal 515 , and is positioned as close to lower surface 515 G of anode terminal 515 as possible. Distance L 3 between surface 516 G of cathode terminal 516 and surface 515 G of anode terminal 515 is not less than 1 mm, and is preferably 1 mm. The distance being less than 1 mm may cause a current leakage across the surfaces. Lower surface 516 G of cathode terminal 516 functions as a mounting surface to be mounted on a mount body. Cathode terminal 516 includes thick portion 516 E having surface 516 G, and thin portion 516 A. Thin portion 516 A is thinner than thick portion 516 E, and extends from thick portion 516 E in a direction opposite to anode terminal 515 . Surface 516 K of thin portion 516 A opposite to the surface of the thin portion facing capacitor elements 501 is covered with resin package 512 and does not expose, not functioning as a mounting surface to be mounted on the mount body. Cathode terminal 516 includes mounting portion 516 C at one end of thin portion 516 A opposite to anode terminal 515 . Mounting portion 516 A has lower surface 516 L functioning as a mounting surface when the capacitor is mounted. Surface 516 L is flush with surfaces 515 G and 516 G. Mounting portion 516 C extends outward to provide protruding portion 516 D of cathode terminal 516 protruding from resin package 512 . Protruding portion 516 D corresponds to protruding portion 514 D of cathode terminal 514 of Embodiment 3. Protruding portion 516 D is bent upward along the side surface (an exterior surface) of resin package 512 , having a shape extending along an exterior of resin package 512 .
Mounting portion 516 C of cathode terminal 516 allows solid electrolytic capacitor 5103 according to Embodiment 4 to have the mounting surfaces provided at the both ends, i.e., under anode terminal 515 and cathode terminal 516 , thus allowing the capacitor to be mounted stably to the mount body
Protruding portions 515 C and 516 D extend from resin package 512 and along its exterior surfaces. This structure allows solder fillets to be easily observable from above when the capacitor is soldered to be mounted to the mount body, thereby providing the capacitor with a high reliability of soldering.
Solid electrolytic capacitor 5103 according to Embodiment has a small equivalent series resistance (ESR) and a small equivalent series inductance (ESL) similarly to solid electrolytic capacitor 5101 of Embodiment 2. The ESL of solid electrolytic capacitor 5103 of Embodiment 4 was 500 pH, which is one third of an ESL of 1500 pH of conventional solid electrolytic capacitor 1100 shown in FIGS. 22 to 24.
FIGS. 9A to 9D show solid electrolytic capacitor 5104 according to Exemplary Embodiment 5 of the invention. FIG. 9B is a front view of solid electrolytic capacitor 5104 . FIG. 9A, FIG. 9C and FIG. 9D are a plan view seen from direction IXA, a bottom view seen from direction IXC, and a side view seen from direction IXD of solid electrolytic capacitor 5104 shown in FIG. 9B. The same components as those of Embodiment 4 will be denoted by the same reference numerals, and their detailed description will be omitted.
Lower surface 517 G of cathode terminal 517 opposite to surface 517 F facing capacitor elements 501 is arranged to be flush with lower surface 515 G of anode terminal 515 , and is positioned as close to lower surface 515 G of anode terminal 515 as possible. Distance L 4 between surface 517 G of cathode terminal 517 and surface 515 G of anode terminal 515 is not less than 1 mm, and is preferably 1 mm. The distance being less than 1 mm may cause a current leakage across the surfaces. Cathode terminal 517 includes thick portion 517 E having surface 517 G, and thin portions 517 A. Thin portions 517 A are thinner than thick portion 517 E, and are connected to both sides of thick portion 517 E. Surface 517 K of cathode terminal 517 opposite to surface 517 F is covered with resin package 512 and does not expose, thus not functioning as a mounting surface to be mounted onto a mount body. Cathode terminal 517 includes protruding portion 517 C at an end of thin portions 517 A opposite to anode terminal 515 . Lower surface 517 G of cathode terminal 517 extends to an end of the surface opposite to anode terminal 515 . Thin portions 517 A are provided at two sides of cathode terminal 517 in direction D 502 perpendicular to direction D 501 in which anode terminal 515 and cathode terminal 517 are arranged. That is, thick portion 517 E of cathode terminal 517 is provided between thin portions 517 A, and thin portions 517 A and thick portion 517 E are arranged in direction D 502 .
In anode terminal 515 , thick portion 515 E is provide between thin portions 515 A, so that thin portions 515 A and thick portion 515 E are arranged in direction D 502 .
In addition to advantages of solid electrolytic capacitor 5103 of Embodiment 4, solid electrolytic capacitor 5104 has cathode terminal 517 easily formed, and is stably mountable to a mount body.
Solid electrolytic capacitor 5104 of Embodiment 5, similarly to solid electrolytic capacitor 5101 of Embodiment 2, has a small equivalent series resistance (ESR) and a small equivalent series inductance (ESL). The ESL of solid electrolytic capacitor 5104 of Embodiment 5 was 500 pH, which is one third of an ESL of 1500 pH of conventional solid electrolytic capacitor 1100 shown in FIGS. 22 to 24.
FIGS. 10A to 10D show solid electrolytic capacitor 6101 according to Exemplary Embodiment 6 of the present invention. FIG. 10B is a front view of solid electrolytic capacitor 6101 . FIGS. 10A, 10 C, and 10 D are a plan view seen from direction XA, a bottom view seen from direction XC, and a side view seen from direction XD of solid electrolytic capacitor 6101 shown in FIG. 10B. FIG. 11 is a perspective view of capacitor element 601 of solid electrolytic capacitor 6101 .
As shown in FIG. 11, capacitor element 601 has a flat plate shape. A surface of anode body 602 made of valve metal, such as aluminum foil is roughened and anodized, providing dielectric oxide layer 602 A on the surface. Resist 603 having an insulating property is provided on dielectric oxide layer 602 A to divide anode body 602 into cathode portion 605 and anode portion 604 . Solid electrolyte layer 606 is provided on dielectric oxide layer 602 A of cathode portion 605 , and cathode layer 607 made of carbon and silver paste is then placed on solid electrolyte layer 606 .
According to Embodiment 6, five capacitor elements 601 are stacked so that anode portion 604 of one of capacitor elements 601 is positioned on anode lead frame 608 . Guides 608 A at both side ends of anode lead frame 608 are folded to wrap anode portions 604 of all five capacitor elements 601 , and joined unitarily to anode portions 604 at junctions 608 B by laser welding.
Cathode portions 605 of the five stacked capacitor elements 601 are placed over cathode lead frame 609 via a conductive adhesive. Five capacitor elements 601 are positioned and fixed by guides 609 A at both side ends and guide 609 B at a distal end of cathode lead frame 609 , and joined unitarily. Capacitor elements 601 , anode lead frame 608 , and cathode lead frame 609 unitarily assembled in the above manner provide capacitor element unit 6101 A.
Anode terminal 610 has thick portion 610 E at the center thereof and thin portions 610 A. Thin portions 610 A are thinner than thick portion 610 E, and connected to both sides of thick portion 610 E. Thin portions 610 A are formed in anode terminal 610 by providing recesses 610 H in surface 610 G opposite to surface 610 F facing capacitor elements 601 . Surface 610 F of anode terminal 610 including thick portion 610 E and thin portions 610 A is flat. Thin portions 610 A have portions surface 610 F of anode terminal 610 , and thick portion 610 E has a portion of surface 610 F. Anode lead frame 608 of capacitor element unit 6101 A is placed on surface 610 F of anode terminal 610 , and is connected to anode terminal 610 at junctions 610 B inside thin portions 610 A by laser welding.
Surface 611 G of cathode terminal 611 opposite to surface 611 F facing capacitor elements 601 is flush with surface 610 G of anode terminal 610 . Surface 611 G of cathode terminal 611 is arranged as close to surface 610 G of anode terminal 610 as possible. Distance L 5 between surface 611 G of cathode terminal 611 and surface 610 G of anode terminal 610 is not less than 1 mm, and preferably is 1 mm. The distance being less than 1 mm may cause a current leakage across the surfaces. Cathode terminal 611 includes thick portion 611 E having surface 611 G, and thin portion 611 A. Thin portion 611 A is thinner than thick portion 611 E, and extends in a direction opposite to anode terminal 610 . Surface 611 F of cathode terminal 611 including thick portion 611 E and thin portion 611 A is flat. Thin portion 611 A has a portion of surface 611 F of cathode terminal 611 , and thick portion 611 E has a portion of surface 611 F. Surface 611 K of thin portion 611 A opposite to surface 611 F is covered with resin package 612 and does not expose, thus not functioning as a mounting surface to be mounted to a mount body. Cathode lead frame 609 of capacitor element unit 6101 A is placed on surface 611 F of cathode terminal 611 , and is connected to cathode terminal 611 at junctions 611 B inside thin portion 611 A by laser welding.
Resin package 612 having an insulating property accommodates capacitor element unit 6101 A unitarily so that surface 610 G of anode terminal 610 and surface 611 G of cathode terminal 611 expose to the outside. According to Embodiment 6, resin package 612 is made of epoxy resin.
FIG. 12A is a plan view of substrate 613 having a hoop shape for providing plural anode terminals 610 and cathode terminals 611 . FIG. 12B is a cross sectional view of substrate 613 at line 12 B- 12 B shown in FIG. 12A. Substrate 613 is made of copper alloy, and has feed holes 613 A formed therein for intermittent feeding. Plural anode terminals 610 and cathode terminals 611 are formed consecutively in substrate 613 at predetermined intervals. Plural capacitor element units 6101 A are placed on and joined to respective ones of plural anode terminals 610 and cathode terminals 611 , and are covered with resin packages 612 , respectively. Anode terminals 610 and cathode terminals 611 are then removed from substrate 613 to provide plural chip capacitors 6101 .
Substrate 613 having plural anode terminals 610 and cathode terminals 611 formed therein is formed by etching a metal plate. The etching provides simultaneously thin portions 610 A and 611 A by removing unnecessary portions and thinning the both sides of anode terminals 610 and cathode terminals 611 . Thickness difference 610 J between thin portion 610 A and thick portion 610 E and thickness difference 611 J between thin portion 611 A and thick portion 611 E are determined to be not less than 80 μm. This dimension of differences 610 J and 611 J is necessary for allowing resin package 612 to flow sufficiently in recesses 610 H and on surface 611 K when capacitor element unit 6101 A is accommodated.
Solid electrolytic capacitor 6101 according to Embodiment 6 allows both anode portion 604 and cathode portion 605 of capacitor element 601 to be drawn to the outside in a short distance through anode terminal 610 and cathode terminal 611 having flat plate shapes. Further, surface 611 G of cathode terminal 611 is arranged as close to surface 610 G of anode terminal 610 as possible in order to reduce the distance between anode terminal 610 and cathode terminal 611 to a shortest possible value, thereby providing the capacitor with a small equivalent series resistance (ESR) and a small equivalent series inductance (ESL). The ESL of solid electrolytic capacitor 6101 of Embodiment 6 was 500 pH, which is about one third of an ESL of 1500 pH of conventional solid electrolytic capacitor 1100 shown in FIGS. 22 to 24.
Anode terminal 610 and cathode terminal 611 are connected with anode lead frame 608 and cathode lead frame 609 of capacitor element unit 6101 A at junctions 610 B and 611 B inside thin portions 610 A and 611 A by laser welding, respectively. Welding spots of these junctions are covered with resin package 612 , providing an excellent external finish. This avoids a possibility of mounting defect attributable to improper contact caused by the welding spots in a mounting process, thereby providing the capacitor with a high reliability.
According to Embodiment 6, anode body 602 of capacitor element 601 is made of aluminum foil, but is not limited to it. The anode body may be made of other valve metal, such as foil or a sintered body of tantalum or niobium, a combination of them.
Substrate 613 has the hoop shape made of copper alloy to obtain anode terminals 610 and cathode terminals 611 , but may be made of other material and may have another shape.
Thin portions 610 A and 611 A of anode terminals 610 and cathode terminals 611 are formed by the etching. The thin portions may be made by press forming.
According to Embodiment 6, plural capacitor elements 601 are stacked and jointed to anode lead frame 608 and cathode lead frame 609 to provide capacitor element unit 6101 A, and are then connected to anode terminal 610 and cathode terminal 611 . However, the structure is not limited to that of this embodiment. One or more capacitor elements 601 may be connected directly to anode terminal 610 and cathode terminal 611 . This can further reduce the ESL. The number of capacitor elements 601 provided in capacitor element unit 6101 A is not necessarily five, and may be determined to provide a predetermined capacitance.
FIGS. 13A to 13D show solid electrolytic capacitor 6102 according to Exemplary Embodiment 7 of the invention. FIG. 13B is a front view of solid electrolytic capacitor 6102 . FIGS. 13A, 13 C, and 13 D are a plan view seen from direction XIIIA, a bottom view seen from direction XIIIC, and a side view seen from direction XIIID of solid electrolytic capacitor 6102 shown in FIG. 13B. The same components as those of Embodiment 6 will be denoted by the same reference numerals, and their detailed description will be omitted.
Lower surface 614 G of cathode terminal 614 is arranged to be flush with anode terminal 610 , and is positioned as close to lower surface 610 G of anode terminal 610 as possible. Surface 610 G functions as a mounting surface to be mounted to a mount body, such as a wiring board. Distance L 6 between surface 614 G of cathode terminal 614 and surface 610 G of anode terminal 610 is not less than 1 mm, and is preferably 1 mm. The distance being less than 1 mm may cause a current leakage across the surfaces. Cathode terminal 614 includes thick portion 614 E having surface 614 G, and thin portion 614 A. Thin portion 614 A is thinner than thick portion 614 E, and extends from thick portion 614 E in a direction opposite to anode terminal 610 . Surface 614 K of thin portion 614 A opposite to a surface facing capacitor elements 601 is covered with resin package 612 and does not expose, thus not functioning as a mounting surface to be mounted on the mount body. Cathode terminal 614 includes mounting portion 614 C at one end of thin portion 614 A opposite to anode terminal 610 . Mounting portion 614 C has lower surface 614 L functioning as a mounting surface when the capacitor is mounted. Surface 614 L is flush with surfaces 610 G and 614 G.
Mounting portion 614 C of cathode terminal 614 allows solid electrolytic capacitor 6102 according to Embodiment 7 to have the mounting surfaces formed at both ends, i.e., under anode terminal 610 and cathode terminal 614 , thereby allowing the capacitor to be mounted stably to the mount body
Solid electrolytic capacitor 6102 according to Embodiment 7 has a small equivalent series resistance (ESR) and a small equivalent series inductance (ESL), similarly to solid electrolytic capacitor 6101 of Embodiment 7. The ESL of solid electrolytic capacitor 6102 of Embodiment 7 was 500 pH, which is one third of an ESL of 1500 pH of conventional solid electrolytic capacitor 1100 shown in FIGS. 22 to 24.
FIGS. 14A to 14D show solid electrolytic capacitor 6103 according to Exemplary Embodiment 8 of this invention. FIG. 14B is a front view of solid electrolytic capacitor 6103 . FIGS. 14A, 14 C, and 14 D are a plan view seen from direction XIVA, a bottom view seen from direction XIVC, and a side view seen from direction XIVD of solid electrolytic capacitor 6103 shown in FIG. 14B. The same components as those of Embodiment 6 will be denoted by the same reference numerals, and their detailed description will be omitted.
Lower surface 615 G of cathode terminal 615 opposite to surface 615 F facing capacitor elements 601 is arranged to be flush with lower surface 610 G of anode terminal 610 , and is positioned as close to lower surface 610 G of anode terminal 610 as possible. Distance L 7 of between surface 615 G of cathode terminal 615 and surface 610 G of anode terminal 610 is not less than 1 mm, and is preferably 1 mm. The distance being less than 1 mm may cause a current leakage across the surfaces. Cathode terminal 615 includes thick portion 615 E having surface 615 G, and thin portions 615 A. Thin portions 615 A are thinner than thick portion 615 E, and are connected to both sides of thick portion 615 E. Surface 615 K of cathode terminal 615 opposite to surface 615 F is covered with resin package 612 and does not expose, thus not functioning as a mounting surface to be mounted onto a mount body. Lower surface 615 G of cathode terminal 615 extends to an end thereof opposite to anode terminal 610 , and thin portions 615 A are provided at two sides of cathode terminal 615 in direction D 602 perpendicular to direction D 601 in which anode terminal 610 and cathode terminal 615 are arranged. Thick portion 615 E is provided between thin portions 615 A so that thin portions 615 A and thick portion 615 E are arranged in direction D 602 . Thick portion 615 E of cathode terminal 615 has portion 5615 E facing anode terminal 610 and has portion 6615 E extending from portion 5615 E toward a direction opposite to anode terminal 610 . Portion 6615 E has a width narrower than that of portion 5615 E. That is, thick portion 615 E and surface 615 G functioning as a mounting surface are arranged substantially in a “T” shape.
In anode terminal 610 , thick portion 610 E are provided between thin portions 610 A, and thin portions 610 A and thick portion 610 E are arranged in direction D 602 .
In addition to advantages of solid electrolytic capacitor 6102 of Embodiment 7, solid electrolytic capacitor 6103 includes cathode terminal 615 easily manufactured, and is stably mountable to a mount body.
Solid electrolytic capacitor 6103 of Embodiment 8 has a small equivalent series resistance (ESR) and a small equivalent series inductance (ESL) similarly to solid electrolytic capacitor 6101 of Embodiment 6. The ESL of solid electrolytic capacitor 6103 of Embodiment 8 was 500 pH, which is one third of an ESL of 1500 pH of conventional solid electrolytic capacitor 1100 shown in FIGS. 22 to 24.
FIGS. 15A to 15D show solid electrolytic capacitor 6104 according to Exemplary Embodiment 9 of the invention. FIG. 15B is a front view of solid electrolytic capacitor 6104 . FIGS. 15A, 15 C, and 15 D are a plan view seen from direction XVA, a bottom view seen from direction XVC, and a side view seen from direction XVD of solid electrolytic capacitor 6104 shown in FIG. 15B. The same components as those of Embodiment 6 will be denoted by the same reference numerals, and their detailed description will be omitted.
Anode terminal 616 has thick portion 616 E at the center thereof and thin portions 616 A. Thin portions 616 A are thinner than thick portion 616 E, and are provided at both sides of thick portion 616 E. Thin portions 616 A in anode terminal 616 are formed by providing recesses 616 H in surface 616 G opposite to surface 616 F facing capacitor elements 601 . Surface 616 F of anode terminal 616 including thick portion 616 E and thin portions 616 A is flat. Thin portions 616 A have portions of surface 616 F of anode terminal 616 , and thick portion 616 E has a portion of surface 616 F. Anode lead frame 608 of capacitor element unit 6101 A is placed on surface 616 F of anode terminal 616 , and is connected to anode terminal 616 at junctions 616 B inside thin portions 616 A by laser welding. Surface 616 G of anode terminal 616 extends outward to provide protruding portion 616 C protruding from resin package 612 . Surface 616 G functions a mounting surface when the capacitor is mounted onto a mount body, such as a wiring board.
Surface 617 G of cathode terminal 617 opposite to surface 617 F facing capacitor elements 601 is arranged to be flush with surface 616 G of anode terminal 616 . Surface 617 G of cathode terminal 617 is positioned as close to surface 616 G of anode terminal 616 as possible. Distance L 8 between surface 617 G of cathode terminal 617 and surface 616 G of anode terminal 616 is not less than 1 mm, and preferably is 1 mm. The distance being less than 1 mm may cause a current leakage across the surfaces. Cathode terminal 617 includes thick portion 617 E having surface 617 G, and thin portion 617 A. This portion 617 A is thinner than thick portion 617 E, and extends from thick portion 617 E in a direction opposite to anode terminal 616 . Surface 617 F of cathode terminal 617 including thick portion 617 E and thin portion 617 A is flat. Thin portion 617 A has a portion of surface 617 F of cathode terminal 617 , and thick portion 617 E has a portion of surface 617 F. Surface 617 K of thin portion 617 A opposite to surface 617 F of thin portion 617 A is covered with resin package 612 and does not expose, thus not functioning as a mounting surface arranged to be mounted on the mount body. Cathode lead frame 609 of capacitor element unit 6101 A is placed on surface 617 F of cathode terminal 617 , and is connected to cathode terminal 617 at junctions 617 B inside thin portion 617 A by laser welding. Lower surface 617 G functioning as a mounting surface of cathode terminal 617 extends so that thick portion 617 E has protruding portions 617 C protruding from resin package 612 . That is, thick portion 617 E extends so that the thick portion protrudes from resin package 612 in direction D 604 perpendicular to direction D 603 in which anode terminal 616 and cathode terminal 617 are arranged.
Protruding portion 616 C of anode terminal 616 and protruding portions 617 C of cathode terminal 617 allows solder fillets to be easily observable from above when capacitor 6104 is soldered to be mounting to the mount body, thereby providing the capacitor with a high reliability of soldering.
FIGS. 16A to 16D show solid electrolytic capacitor 6105 according to Exemplary Embodiment 10 of this invention. FIG. 16B is a front view of solid electrolytic capacitor 6105 . FIGS. 16A, 16 C, and 16 D are a plan view seen from direction XVIA, a bottom view seen from direction XVIC, and a side view seen from direction XVID of solid electrolytic capacitor 6105 shown in FIG. 16B. The same components as those of Embodiment 9 will be denoted by the same reference numerals, and their detailed description will be omitted.
Lower surface 618 G of cathode terminal 618 is arranged to be flush with lower surface 616 G of anode terminal 616 , and is positioned as close to lower surface 616 G of anode terminal 616 as possible. Distance L 9 between surface 618 G of cathode terminal 618 and surface 616 G of anode terminal 616 is not less than 1 mm, and preferably is 1 mm. The distance being less than 1 mm may cause a current leakage across the surfaces. Surface 616 G functions as a mounting surface when the capacitor is mounted onto a mount body, such as a wiring board. Cathode terminal 618 includes thick portion 618 E having surface 618 G, and thin portion 618 A. Thin portion 618 A is thinner than thick portion 618 E, and extends from thick portion 618 E in a direction opposite to anode terminal 616 . Surface 618 K of thin portion 618 A opposite to a surface facing capacitor elements 601 is covered with resin package 612 and does not expose, thus not functioning as a mounting surface arranged to be mounted on the mount body. Cathode terminal 618 includes protruding portion 618 D at an end of thin portion 618 A opposite to anode terminal 616 . Protruding portion 618 D has lower surface 618 L functioning as a mounting surface when the capacitor is mounted. Surface 618 L is flush with surfaces 616 G and 618 G. Surface 618 G functioning as a mounting surface of cathode terminal 618 extends outward, so that cathode terminal 618 has protruding portions 618 C protruding from resin package 612 . Thick portion 618 E having surface 618 G extends to provide protruding portion 618 D protruding from resin package 612 .
Solid electrolytic capacitor 6105 of Embodiment 10, protruding portion 616 C of anode terminal 616 and protruding portions 618 C and 618 D of cathode terminal 618 allow solder fillets to be easily observable from above when capacitor 6105 is soldered to be mounted to the mount body, thereby providing a high reliability of soldering.
FIGS. 17A to 17D show solid electrolytic capacitor 6106 according to Exemplary Embodiment 11 of this invention. FIG. 17B is a front view of solid electrolytic capacitor 6106 . FIGS. 17A, 17 C, and 17 D are a plan view seen from direction XVIIA, a bottom view seen from direction XVIIC, and a side view seen from direction XVIID of solid electrolytic capacitor 6106 shown in FIG. 17B. The same components as those of Embodiment 8 will be denoted by the same reference numerals, and their detailed description will be omitted.
Lower surface 619 G of cathode terminal 619 opposite to surface 619 F facing capacitor elements 601 is arranged to be flush with lower surface 616 G of anode terminal 616 , and is positioned as close to lower surface 616 G of anode terminal 616 as possible. Distance L 10 between surface 619 G of cathode terminal 619 and surface 616 G of anode terminal 616 is less than 1 mm, and preferably is 1 mm. The distance being less than 1 mm may cause a current leakage across the surfaces. Surface 616 G functions as a mounting surface when the capacitor is mounted to a mount body, such as a wiring board. Cathode terminal 619 includes thick portion 619 E having surface 619 G, and thin portions 619 A. Thin portions 619 A are thinner than thick portion 619 E, and are connected to both sides of thick portion 619 E. Surfaces 619 K of thin portions 619 A of cathode terminal 619 opposite to surface 619 F is covered with resin package 612 and does not expose, thus not functioning as a mounting surface arranged to be mounted to the mount body. Lower surface 619 G of cathode terminal 619 extends to an end thereof opposite to anode terminal 616 , and thin portions 619 A are provided at two sides of cathode terminal 619 in direction D 606 perpendicular to direction D 605 in which anode terminal 616 and cathode terminal 619 are arranged. That is, thick portion 619 E and lower surface 619 G functioning as a mounting surface of cathode terminal 619 are arranged substantially in a “T”, as sown in FIG. 17C. Thick portion 619 E having lower surface 619 G functioning as the mounting surface of cathode terminal 619 extends outward to provide protruding portions 619 C and 619 D protruding from resin package 612 . That is, thick portion 619 E includes protruding portions 619 C and 619 D which extend in directions D 605 and D 606 perpendicular to direction D 605 in which anode terminal 616 and cathode terminal 619 are arranged, respectively.
Protruding portion 616 C of anode terminal 616 and protruding portions 619 C and 619 D of cathode terminal 619 allows solder fillets to be easily observable from above when capacitor 6106 is soldered to be mounting to the mount body, thereby providing a high reliability of soldering.
FIGS. 18A to 18D show solid electrolytic capacitor 6107 according to Exemplary Embodiment 12 of this invention. FIG. 18B is a front view of solid electrolytic capacitor 6107 . FIGS. 18A, 18 C, and 18 D are a plan view seen from direction XVIIIA, a bottom view seen from direction XVIIIC, and a side view seen from direction XVIIID of solid electrolytic capacitor 6107 shown in FIG. 18B. The same components as those of embodiment 9 will be denoted by the same reference numerals, and their detailed description will be omitted.
Anode terminal 620 has thick portion 620 E at the center thereof and thin portions 620 A. Thin portions 620 A are thinner than thick portion 620 E, and are provided at both sides of thick portion 620 E. Surface 620 F of anode terminal 620 including thick portion 620 E and thin portions 620 A is flat. Thin portions 620 A have portions of surface 620 F of anode terminal 620 , and thick portion 620 E has a portion of surface 620 F. Anode lead frame 608 of capacitor element unit 6101 A is placed on surface 620 F of anode terminal 620 , and is connected to anode terminal 620 at junctions 620 B inside thin portions 620 A by laser welding. Surface 620 G of anode terminal 620 extending outward provides protruding portion 620 C protruding from resin package 612 . Protruding portion 620 C is bent upward along a side surface (i.e., an exterior surface) of resin package 612 , so as to have a shape extending along an exterior of resin package 612 .
Surface 621 G of cathode terminal 621 opposite to surface 621 F facing capacitor elements 601 is arranged to be flush with surface 620 G of anode terminal 620 . Cathode terminal 621 includes thick portion 621 E having surface 621 G, and thin portion 621 A. Thin portion 621 A is thinner than thick portion 621 E, and extends from thick portion 621 E in a direction opposite to anode terminal 620 . Surface 621 F of cathode terminal 621 including thick portion 621 E and thin portion 621 A is flat. Thin portion 621 A has a portion of surface 621 F of cathode terminal 621 , and thick portion 621 E has a portion of surface 621 F. Cathode lead frame 609 of capacitor element unit 6101 A is placed on surface 621 F of cathode terminal 621 , and is connected to cathode terminal 621 at junctions 621 B inside thin portion 621 A by laser welding. Thick portion 621 E having lower surface 621 G functioning as a mounting surface of cathode terminal 621 extends to outside of resin package 512 to provide protruding portions 621 C. Protruding portions 621 C are bent upward along side surfaces (exterior surfaces) of resin package 612 , so as to have shapes extending along an exterior of resin package 612 .
Protruding portion 620 C of anode terminal 620 and protruding portions 621 C of cathode terminal 621 allows solder fillets to be easily observable from above when capacitor 6107 is soldered to be mounted to a mount body, thereby providing the capacitor with a high reliability of soldering.
FIG. 18E is a perspective view of another solid electrolytic capacitor 6207 according to Embodiment 12. Solid electrolytic capacitor 6207 includes resin package 612 A having a shape different from that of resin package 612 of solid electrolytic capacitor 6107 , while other components are identical to those of capacitor 6107 . Resin package 612 A has recesses 612 B and 612 C in which protruding portion 620 C of anode terminal 620 and protruding portions 621 C of cathode terminal 621 are positioned, respectively. This structure allows solid electrolytic capacitor 6207 to have s small size without increasing its dimensions.
FIGS. 19A to 19D show solid electrolytic capacitor 6108 according to Exemplary Embodiment 13 of this invention. FIG. 19B is a front view of solid electrolytic capacitor 6108 . FIGS. 19A, 19 C, and 19 D are a plan view seen from direction XIXA, a bottom view seen from direction XIXC, and a side view seen from direction XIXD of solid electrolytic capacitor 6108 shown in FIG. 19B. The same components as those of Embodiment 12 will be denoted by the same reference numerals, and their detailed description will be omitted.
Surface 622 G of cathode terminal 622 opposite to surface 622 F facing capacitor elements 601 is arranged to be flush with surface 620 G of anode terminal 620 . Cathode terminal 622 includes thick portion 622 E having surface 622 G, and thin portion 622 A. Thin portion 622 A is thinner than thick portion 622 E, and extends from thick portion 622 E in a direction opposite to anode terminal 620 . Surface 622 F of cathode terminal 622 including thick portion 622 E and thin portion 622 A is flat. Thin portion 622 A has a portion of surface 622 F of cathode terminal 622 , and thick portion 622 E has a portion of surface 622 F. Cathode lead frame 609 of capacitor element unit 6101 A is placed on surface 622 F of cathode terminal 622 , and is connected to cathode terminal 622 at junctions 622 B inside thin portion 622 A by laser welding. Thick portion 622 E having lower surface 622 G functioning as a mounting surface of cathode terminal 622 extends outside of resin package 612 to provide protruding portions 622 C. Protruding portions 622 C are bent upward along side surfaces (exterior surfaces) of resin package 612 , so as to have shapes extending along an exterior of resin package 612 . Cathode terminal 622 includes protruding portion 622 D having lower surface 622 L functioning as a mounting surface when the capacitor is mounted. Protruding portion 622 D extends from resin package 612 at an end of thin portion 622 A opposite to anode terminal 620 . Surface 622 L is flush with surfaces 620 G and 622 G. Protruding portion 622 D is bent upward along the side surfaces (the exterior surfaces) of resin package 612 , so as to have a shape extending along the exterior of resin package 612 .
In solid electrolytic capacitor 6108 of Embodiment 13, protruding portion 620 C of anode terminal 620 and protruding portions 622 C and 622 D of cathode terminal 622 allows solder fillets to be easily observable from above when capacitor 6108 is soldered to be mounted to the mount body, thereby providing the capacitor with a high reliability of soldering.
Similarly to solid electrolytic capacitor 6207 shown in FIG. 18E, resin package 612 may have recesses provided therein in which protruding portions 620 C, 622 C, and 622 D extended from the exterior of resin package 612 are positioned, thereby allowing the capacitor to have a small size.
FIGS. 20A to 20D show solid electrolytic capacitor 6109 according to Exemplary Embodiment 14 of this invention. FIG. 20B is a front view of solid electrolytic capacitor 6109 . FIGS. 20A, 20 C, and 20 D are a plan view seen from direction XXA, a bottom view seen from direction XXC, and a side view seen from direction XXD of solid electrolytic capacitor 6109 shown in FIG. 20B. The same components as those of Embodiment 13 will be denoted by the same reference numerals, and their detailed description will be omitted.
Lower surface 623 G of cathode terminal 623 opposite to upper surface 623 F facing capacitor elements 601 is arranged to be flush with lower surface 620 G of anode terminal 620 . Lower surface 620 G functions as a mounting surface arranged to be mounted onto a mount body, such as a wiring board. Cathode terminal 623 includes thick portion 623 E having surface 623 G, and thin portions 623 A. Thin portions 623 A are thinner than thick portion 623 E, and are connected to both sides of thick portion 623 E. Surface 623 F of cathode terminal 623 including thick portion 623 E and thin portions 623 A is flat. Thin portions 623 A have portions of surface 623 F of cathode terminal 623 , and thick portion 623 E has a portion of surface 623 F. Lower surface 623 G of cathode terminal 623 extends to an end thereof opposite to anode terminal 620 , and thin portions 623 A are provided at two sides of cathode terminal 623 in direction D 608 perpendicular to direction D 607 in which anode terminal 620 and cathode terminal 623 are arranged. That is, thick portion 623 E and lower surface 623 G functioning as a mounting surface of cathode terminal 623 are arranged substantially in a “T” shape, as shown in FIG. 20C. Thick portion 623 E having lower surface 623 G functioning as the mounting surface of cathode terminal 623 extends outward to provide protruding portions 623 C and 623 D protruding from resin package 612 . That is, thick portion 623 E includes protruding portions 623 C and 623 D which extend in directions D 607 and D 608 perpendicular to direction D 607 in which anode terminal 620 and cathode terminal 623 are arranged, respectively. Protruding portions 623 C and 623 D are bent upward along side surfaces (exterior surfaces) of resin package 612 , so as to have shapes extending along an exterior of resin package 612 .
In solid electrolytic capacitor 6109 of Embodiment 14, protruding portion 620 C of anode terminal 620 and protruding portions 623 C and 623 D of cathode terminal 623 allow solder fillets to be easily observable from above when capacitor 6109 is soldered to be mounted to the mount body, thereby providing the capacitor with a high reliability of soldering.
Similarly to solid electrolytic capacitor 6207 shown in FIG. 18E, resin package <